net/x25/af_x25.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *      X.25 Packet Layer release 002
   4  *
   5  *      This is ALPHA test software. This code may break your machine,
   6  *      randomly fail to work with new releases, misbehave and/or generally
   7  *      screw up. It might even work.
   8  *
   9  *      This code REQUIRES 2.1.15 or higher
  10  *
  11  *      History
  12  *      X.25 001        Jonathan Naylor Started coding.
  13  *      X.25 002        Jonathan Naylor Centralised disconnect handling.
  14  *                                      New timer architecture.
  15  *      2000-03-11      Henner Eisen    MSG_EOR handling more POSIX compliant.
  16  *      2000-03-22      Daniela Squassoni Allowed disabling/enabling of
  17  *                                        facilities negotiation and increased
  18  *                                        the throughput upper limit.
  19  *      2000-08-27      Arnaldo C. Melo s/suser/capable/ + micro cleanups
  20  *      2000-09-04      Henner Eisen    Set sock->state in x25_accept().
  21  *                                      Fixed x25_output() related skb leakage.
  22  *      2000-10-02      Henner Eisen    Made x25_kick() single threaded per socket.
  23  *      2000-10-27      Henner Eisen    MSG_DONTWAIT for fragment allocation.
  24  *      2000-11-14      Henner Eisen    Closing datalink from NETDEV_GOING_DOWN
  25  *      2002-10-06      Arnaldo C. Melo Get rid of cli/sti, move proc stuff to
  26  *                                      x25_proc.c, using seq_file
  27  *      2005-04-02      Shaun Pereira   Selective sub address matching
  28  *                                      with call user data
  29  *      2005-04-15      Shaun Pereira   Fast select with no restriction on
  30  *                                      response
  31  */
  32
  33 #define pr_fmt(fmt) "X25: " fmt
  34
  35 #include <linux/module.h>
  36 #include <linux/capability.h>
  37 #include <linux/errno.h>
  38 #include <linux/kernel.h>
  39 #include <linux/sched/signal.h>
  40 #include <linux/timer.h>
  41 #include <linux/string.h>
  42 #include <linux/net.h>
  43 #include <linux/netdevice.h>
  44 #include <linux/if_arp.h>
  45 #include <linux/skbuff.h>
  46 #include <linux/slab.h>
  47 #include <net/sock.h>
  48 #include <net/tcp_states.h>
  49 #include <linux/uaccess.h>
  50 #include <linux/fcntl.h>
  51 #include <linux/termios.h>      /* For TIOCINQ/OUTQ */
  52 #include <linux/notifier.h>
  53 #include <linux/init.h>
  54 #include <linux/compat.h>
  55 #include <linux/ctype.h>
  56
  57 #include <net/x25.h>
  58 #include <net/compat.h>
  59
  60 int sysctl_x25_restart_request_timeout = X25_DEFAULT_T20;
  61 int sysctl_x25_call_request_timeout    = X25_DEFAULT_T21;
  62 int sysctl_x25_reset_request_timeout   = X25_DEFAULT_T22;
  63 int sysctl_x25_clear_request_timeout   = X25_DEFAULT_T23;
  64 int sysctl_x25_ack_holdback_timeout    = X25_DEFAULT_T2;
  65 int sysctl_x25_forward                 = 0;
  66
  67 HLIST_HEAD(x25_list);
  68 DEFINE_RWLOCK(x25_list_lock);
  69
  70 static const struct proto_ops x25_proto_ops;
  71
  72 static const struct x25_address null_x25_address = {"               "};
  73
  74 #ifdef CONFIG_COMPAT
  75 struct compat_x25_subscrip_struct {
  76         char device[200-sizeof(compat_ulong_t)];
  77         compat_ulong_t global_facil_mask;
  78         compat_uint_t extended;
  79 };
  80 #endif
  81
  82
  83 int x25_parse_address_block(struct sk_buff *skb,
  84                 struct x25_address *called_addr,
  85                 struct x25_address *calling_addr)
  86 {
  87         unsigned char len;
  88         int needed;
  89         int rc;
  90
  91         if (!pskb_may_pull(skb, 1)) {
  92                 /* packet has no address block */
  93                 rc = 0;
  94                 goto empty;
  95         }
  96
  97         len = *skb->data;
  98         needed = 1 + ((len >> 4) + (len & 0x0f) + 1) / 2;
  99
 100         if (!pskb_may_pull(skb, needed)) {
 101                 /* packet is too short to hold the addresses it claims
 102                    to hold */
 103                 rc = -1;
 104                 goto empty;
 105         }
 106
 107         return x25_addr_ntoa(skb->data, called_addr, calling_addr);
 108
 109 empty:
 110         *called_addr->x25_addr = 0;
 111         *calling_addr->x25_addr = 0;
 112
 113         return rc;
 114 }
 115
 116
 117 int x25_addr_ntoa(unsigned char *p, struct x25_address *called_addr,
 118                   struct x25_address *calling_addr)
 119 {
 120         unsigned int called_len, calling_len;
 121         char *called, *calling;
 122         unsigned int i;
 123
 124         called_len  = (*p >> 0) & 0x0F;
 125         calling_len = (*p >> 4) & 0x0F;
 126
 127         called  = called_addr->x25_addr;
 128         calling = calling_addr->x25_addr;
 129         p++;
 130
 131         for (i = 0; i < (called_len + calling_len); i++) {
 132                 if (i < called_len) {
 133                         if (i % 2 != 0) {
 134                                 *called++ = ((*p >> 0) & 0x0F) + '0';
 135                                 p++;
 136                         } else {
 137                                 *called++ = ((*p >> 4) & 0x0F) + '0';
 138                         }
 139                 } else {
 140                         if (i % 2 != 0) {
 141                                 *calling++ = ((*p >> 0) & 0x0F) + '0';
 142                                 p++;
 143                         } else {
 144                                 *calling++ = ((*p >> 4) & 0x0F) + '0';
 145                         }
 146                 }
 147         }
 148
 149         *called = *calling = '\0';
 150
 151         return 1 + (called_len + calling_len + 1) / 2;
 152 }
 153
 154 int x25_addr_aton(unsigned char *p, struct x25_address *called_addr,
 155                   struct x25_address *calling_addr)
 156 {
 157         unsigned int called_len, calling_len;
 158         char *called, *calling;
 159         int i;
 160
 161         called  = called_addr->x25_addr;
 162         calling = calling_addr->x25_addr;
 163
 164         called_len  = strlen(called);
 165         calling_len = strlen(calling);
 166
 167         *p++ = (calling_len << 4) | (called_len << 0);
 168
 169         for (i = 0; i < (called_len + calling_len); i++) {
 170                 if (i < called_len) {
 171                         if (i % 2 != 0) {
 172                                 *p |= (*called++ - '0') << 0;
 173                                 p++;
 174                         } else {
 175                                 *p = 0x00;
 176                                 *p |= (*called++ - '0') << 4;
 177                         }
 178                 } else {
 179                         if (i % 2 != 0) {
 180                                 *p |= (*calling++ - '0') << 0;
 181                                 p++;
 182                         } else {
 183                                 *p = 0x00;
 184                                 *p |= (*calling++ - '0') << 4;
 185                         }
 186                 }
 187         }
 188
 189         return 1 + (called_len + calling_len + 1) / 2;
 190 }
 191
 192 /*
 193  *      Socket removal during an interrupt is now safe.
 194  */
 195 static void x25_remove_socket(struct sock *sk)
 196 {
 197         write_lock_bh(&x25_list_lock);
 198         sk_del_node_init(sk);
 199         write_unlock_bh(&x25_list_lock);
 200 }
 201
 202 /*
 203  *      Kill all bound sockets on a dropped device.
 204  */
 205 static void x25_kill_by_device(struct net_device *dev)
 206 {
 207         struct sock *s;
 208
 209         write_lock_bh(&x25_list_lock);
 210
 211         sk_for_each(s, &x25_list)
 212                 if (x25_sk(s)->neighbour && x25_sk(s)->neighbour->dev == dev)
 213                         x25_disconnect(s, ENETUNREACH, 0, 0);
 214
 215         write_unlock_bh(&x25_list_lock);
 216 }
 217
 218 /*
 219  *      Handle device status changes.
 220  */
 221 static int x25_device_event(struct notifier_block *this, unsigned long event,
 222                             void *ptr)
 223 {
 224         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
 225         struct x25_neigh *nb;
 226
 227         if (!net_eq(dev_net(dev), &init_net))
 228                 return NOTIFY_DONE;
 229
 230         if (dev->type == ARPHRD_X25
 231 #if IS_ENABLED(CONFIG_LLC)
 232          || dev->type == ARPHRD_ETHER
 233 #endif
 234          ) {
 235                 switch (event) {
 236                 case NETDEV_UP:
 237                         x25_link_device_up(dev);
 238                         break;
 239                 case NETDEV_GOING_DOWN:
 240                         nb = x25_get_neigh(dev);
 241                         if (nb) {
 242                                 x25_terminate_link(nb);
 243                                 x25_neigh_put(nb);
 244                         }
 245                         break;
 246                 case NETDEV_DOWN:
 247                         x25_kill_by_device(dev);
 248                         x25_route_device_down(dev);
 249                         x25_link_device_down(dev);
 250                         break;
 251                 }
 252         }
 253
 254         return NOTIFY_DONE;
 255 }
 256
 257 /*
 258  *      Add a socket to the bound sockets list.
 259  */
 260 static void x25_insert_socket(struct sock *sk)
 261 {
 262         write_lock_bh(&x25_list_lock);
 263         sk_add_node(sk, &x25_list);
 264         write_unlock_bh(&x25_list_lock);
 265 }
 266
 267 /*
 268  *      Find a socket that wants to accept the Call Request we just
 269  *      received. Check the full list for an address/cud match.
 270  *      If no cuds match return the next_best thing, an address match.
 271  *      Note: if a listening socket has cud set it must only get calls
 272  *      with matching cud.
 273  */
 274 static struct sock *x25_find_listener(struct x25_address *addr,
 275                                         struct sk_buff *skb)
 276 {
 277         struct sock *s;
 278         struct sock *next_best;
 279
 280         read_lock_bh(&x25_list_lock);
 281         next_best = NULL;
 282
 283         sk_for_each(s, &x25_list)
 284                 if ((!strcmp(addr->x25_addr,
 285                         x25_sk(s)->source_addr.x25_addr) ||
 286                                 !strcmp(x25_sk(s)->source_addr.x25_addr,
 287                                         null_x25_address.x25_addr)) &&
 288                                         s->sk_state == TCP_LISTEN) {
 289                         /*
 290                          * Found a listening socket, now check the incoming
 291                          * call user data vs this sockets call user data
 292                          */
 293                         if (x25_sk(s)->cudmatchlength > 0 &&
 294                                 skb->len >= x25_sk(s)->cudmatchlength) {
 295                                 if((memcmp(x25_sk(s)->calluserdata.cuddata,
 296                                         skb->data,
 297                                         x25_sk(s)->cudmatchlength)) == 0) {
 298                                         sock_hold(s);
 299                                         goto found;
 300                                  }
 301                         } else
 302                                 next_best = s;
 303                 }
 304         if (next_best) {
 305                 s = next_best;
 306                 sock_hold(s);
 307                 goto found;
 308         }
 309         s = NULL;
 310 found:
 311         read_unlock_bh(&x25_list_lock);
 312         return s;
 313 }
 314
 315 /*
 316  *      Find a connected X.25 socket given my LCI and neighbour.
 317  */
 318 static struct sock *__x25_find_socket(unsigned int lci, struct x25_neigh *nb)
 319 {
 320         struct sock *s;
 321
 322         sk_for_each(s, &x25_list)
 323                 if (x25_sk(s)->lci == lci && x25_sk(s)->neighbour == nb) {
 324                         sock_hold(s);
 325                         goto found;
 326                 }
 327         s = NULL;
 328 found:
 329         return s;
 330 }
 331
 332 struct sock *x25_find_socket(unsigned int lci, struct x25_neigh *nb)
 333 {
 334         struct sock *s;
 335
 336         read_lock_bh(&x25_list_lock);
 337         s = __x25_find_socket(lci, nb);
 338         read_unlock_bh(&x25_list_lock);
 339         return s;
 340 }
 341
 342 /*
 343  *      Find a unique LCI for a given device.
 344  */
 345 static unsigned int x25_new_lci(struct x25_neigh *nb)
 346 {
 347         unsigned int lci = 1;
 348         struct sock *sk;
 349
 350         while ((sk = x25_find_socket(lci, nb)) != NULL) {
 351                 sock_put(sk);
 352                 if (++lci == 4096) {
 353                         lci = 0;
 354                         break;
 355                 }
 356                 cond_resched();
 357         }
 358
 359         return lci;
 360 }
 361
 362 /*
 363  *      Deferred destroy.
 364  */
 365 static void __x25_destroy_socket(struct sock *);
 366
 367 /*
 368  *      handler for deferred kills.
 369  */
 370 static void x25_destroy_timer(struct timer_list *t)
 371 {
 372         struct sock *sk = from_timer(sk, t, sk_timer);
 373
 374         x25_destroy_socket_from_timer(sk);
 375 }
 376
 377 /*
 378  *      This is called from user mode and the timers. Thus it protects itself
 379  *      against interrupt users but doesn't worry about being called during
 380  *      work. Once it is removed from the queue no interrupt or bottom half
 381  *      will touch it and we are (fairly 8-) ) safe.
 382  *      Not static as it's used by the timer
 383  */
 384 static void __x25_destroy_socket(struct sock *sk)
 385 {
 386         struct sk_buff *skb;
 387
 388         x25_stop_heartbeat(sk);
 389         x25_stop_timer(sk);
 390
 391         x25_remove_socket(sk);
 392         x25_clear_queues(sk);           /* Flush the queues */
 393
 394         while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL) {
 395                 if (skb->sk != sk) {            /* A pending connection */
 396                         /*
 397                          * Queue the unaccepted socket for death
 398                          */
 399                         skb->sk->sk_state = TCP_LISTEN;
 400                         sock_set_flag(skb->sk, SOCK_DEAD);
 401                         x25_start_heartbeat(skb->sk);
 402                         x25_sk(skb->sk)->state = X25_STATE_0;
 403                 }
 404
 405                 kfree_skb(skb);
 406         }
 407
 408         if (sk_has_allocations(sk)) {
 409                 /* Defer: outstanding buffers */
 410                 sk->sk_timer.expires  = jiffies + 10 * HZ;
 411                 sk->sk_timer.function = x25_destroy_timer;
 412                 add_timer(&sk->sk_timer);
 413         } else {
 414                 /* drop last reference so sock_put will free */
 415                 __sock_put(sk);
 416         }
 417 }
 418
 419 void x25_destroy_socket_from_timer(struct sock *sk)
 420 {
 421         sock_hold(sk);
 422         bh_lock_sock(sk);
 423         __x25_destroy_socket(sk);
 424         bh_unlock_sock(sk);
 425         sock_put(sk);
 426 }
 427
 428 /*
 429  *      Handling for system calls applied via the various interfaces to a
 430  *      X.25 socket object.
 431  */
 432
 433 static int x25_setsockopt(struct socket *sock, int level, int optname,
 434                           sockptr_t optval, unsigned int optlen)
 435 {
 436         int opt;
 437         struct sock *sk = sock->sk;
 438         int rc = -ENOPROTOOPT;
 439
 440         if (level != SOL_X25 || optname != X25_QBITINCL)
 441                 goto out;
 442
 443         rc = -EINVAL;
 444         if (optlen < sizeof(int))
 445                 goto out;
 446
 447         rc = -EFAULT;
 448         if (copy_from_sockptr(&opt, optval, sizeof(int)))
 449                 goto out;
 450
 451         if (opt)
 452                 set_bit(X25_Q_BIT_FLAG, &x25_sk(sk)->flags);
 453         else
 454                 clear_bit(X25_Q_BIT_FLAG, &x25_sk(sk)->flags);
 455         rc = 0;
 456 out:
 457         return rc;
 458 }
 459
 460 static int x25_getsockopt(struct socket *sock, int level, int optname,
 461                           char __user *optval, int __user *optlen)
 462 {
 463         struct sock *sk = sock->sk;
 464         int val, len, rc = -ENOPROTOOPT;
 465
 466         if (level != SOL_X25 || optname != X25_QBITINCL)
 467                 goto out;
 468
 469         rc = -EFAULT;
 470         if (get_user(len, optlen))
 471                 goto out;
 472
 473         len = min_t(unsigned int, len, sizeof(int));
 474
 475         rc = -EINVAL;
 476         if (len < 0)
 477                 goto out;
 478
 479         rc = -EFAULT;
 480         if (put_user(len, optlen))
 481                 goto out;
 482
 483         val = test_bit(X25_Q_BIT_FLAG, &x25_sk(sk)->flags);
 484         rc = copy_to_user(optval, &val, len) ? -EFAULT : 0;
 485 out:
 486         return rc;
 487 }
 488
 489 static int x25_listen(struct socket *sock, int backlog)
 490 {
 491         struct sock *sk = sock->sk;
 492         int rc = -EOPNOTSUPP;
 493
 494         lock_sock(sk);
 495         if (sk->sk_state != TCP_LISTEN) {
 496                 memset(&x25_sk(sk)->dest_addr, 0, X25_ADDR_LEN);
 497                 sk->sk_max_ack_backlog = backlog;
 498                 sk->sk_state           = TCP_LISTEN;
 499                 rc = 0;
 500         }
 501         release_sock(sk);
 502
 503         return rc;
 504 }
 505
 506 static struct proto x25_proto = {
 507         .name     = "X25",
 508         .owner    = THIS_MODULE,
 509         .obj_size = sizeof(struct x25_sock),
 510 };
 511
 512 static struct sock *x25_alloc_socket(struct net *net, int kern)
 513 {
 514         struct x25_sock *x25;
 515         struct sock *sk = sk_alloc(net, AF_X25, GFP_ATOMIC, &x25_proto, kern);
 516
 517         if (!sk)
 518                 goto out;
 519
 520         sock_init_data(NULL, sk);
 521
 522         x25 = x25_sk(sk);
 523         skb_queue_head_init(&x25->ack_queue);
 524         skb_queue_head_init(&x25->fragment_queue);
 525         skb_queue_head_init(&x25->interrupt_in_queue);
 526         skb_queue_head_init(&x25->interrupt_out_queue);
 527 out:
 528         return sk;
 529 }
 530
 531 static int x25_create(struct net *net, struct socket *sock, int protocol,
 532                       int kern)
 533 {
 534         struct sock *sk;
 535         struct x25_sock *x25;
 536         int rc = -EAFNOSUPPORT;
 537
 538         if (!net_eq(net, &init_net))
 539                 goto out;
 540
 541         rc = -ESOCKTNOSUPPORT;
 542         if (sock->type != SOCK_SEQPACKET)
 543                 goto out;
 544
 545         rc = -EINVAL;
 546         if (protocol)
 547                 goto out;
 548
 549         rc = -ENOBUFS;
 550         if ((sk = x25_alloc_socket(net, kern)) == NULL)
 551                 goto out;
 552
 553         x25 = x25_sk(sk);
 554
 555         sock_init_data(sock, sk);
 556
 557         x25_init_timers(sk);
 558
 559         sock->ops    = &x25_proto_ops;
 560         sk->sk_protocol = protocol;
 561         sk->sk_backlog_rcv = x25_backlog_rcv;
 562
 563         x25->t21   = sysctl_x25_call_request_timeout;
 564         x25->t22   = sysctl_x25_reset_request_timeout;
 565         x25->t23   = sysctl_x25_clear_request_timeout;
 566         x25->t2    = sysctl_x25_ack_holdback_timeout;
 567         x25->state = X25_STATE_0;
 568         x25->cudmatchlength = 0;
 569         set_bit(X25_ACCPT_APPRV_FLAG, &x25->flags);     /* normally no cud  */
 570                                                         /* on call accept   */
 571
 572         x25->facilities.winsize_in  = X25_DEFAULT_WINDOW_SIZE;
 573         x25->facilities.winsize_out = X25_DEFAULT_WINDOW_SIZE;
 574         x25->facilities.pacsize_in  = X25_DEFAULT_PACKET_SIZE;
 575         x25->facilities.pacsize_out = X25_DEFAULT_PACKET_SIZE;
 576         x25->facilities.throughput  = 0;        /* by default don't negotiate
 577                                                    throughput */
 578         x25->facilities.reverse     = X25_DEFAULT_REVERSE;
 579         x25->dte_facilities.calling_len = 0;
 580         x25->dte_facilities.called_len = 0;
 581         memset(x25->dte_facilities.called_ae, '\0',
 582                         sizeof(x25->dte_facilities.called_ae));
 583         memset(x25->dte_facilities.calling_ae, '\0',
 584                         sizeof(x25->dte_facilities.calling_ae));
 585
 586         rc = 0;
 587 out:
 588         return rc;
 589 }
 590
 591 static struct sock *x25_make_new(struct sock *osk)
 592 {
 593         struct sock *sk = NULL;
 594         struct x25_sock *x25, *ox25;
 595
 596         if (osk->sk_type != SOCK_SEQPACKET)
 597                 goto out;
 598
 599         if ((sk = x25_alloc_socket(sock_net(osk), 0)) == NULL)
 600                 goto out;
 601
 602         x25 = x25_sk(sk);
 603
 604         sk->sk_type        = osk->sk_type;
 605         sk->sk_priority    = osk->sk_priority;
 606         sk->sk_protocol    = osk->sk_protocol;
 607         sk->sk_rcvbuf      = osk->sk_rcvbuf;
 608         sk->sk_sndbuf      = osk->sk_sndbuf;
 609         sk->sk_state       = TCP_ESTABLISHED;
 610         sk->sk_backlog_rcv = osk->sk_backlog_rcv;
 611         sock_copy_flags(sk, osk);
 612
 613         ox25 = x25_sk(osk);
 614         x25->t21        = ox25->t21;
 615         x25->t22        = ox25->t22;
 616         x25->t23        = ox25->t23;
 617         x25->t2         = ox25->t2;
 618         x25->flags      = ox25->flags;
 619         x25->facilities = ox25->facilities;
 620         x25->dte_facilities = ox25->dte_facilities;
 621         x25->cudmatchlength = ox25->cudmatchlength;
 622
 623         clear_bit(X25_INTERRUPT_FLAG, &x25->flags);
 624         x25_init_timers(sk);
 625 out:
 626         return sk;
 627 }
 628
 629 static int x25_release(struct socket *sock)
 630 {
 631         struct sock *sk = sock->sk;
 632         struct x25_sock *x25;
 633
 634         if (!sk)
 635                 return 0;
 636
 637         x25 = x25_sk(sk);
 638
 639         sock_hold(sk);
 640         lock_sock(sk);
 641         switch (x25->state) {
 642
 643                 case X25_STATE_0:
 644                 case X25_STATE_2:
 645                         x25_disconnect(sk, 0, 0, 0);
 646                         __x25_destroy_socket(sk);
 647                         goto out;
 648
 649                 case X25_STATE_1:
 650                 case X25_STATE_3:
 651                 case X25_STATE_4:
 652                         x25_clear_queues(sk);
 653                         x25_write_internal(sk, X25_CLEAR_REQUEST);
 654                         x25_start_t23timer(sk);
 655                         x25->state = X25_STATE_2;
 656                         sk->sk_state    = TCP_CLOSE;
 657                         sk->sk_shutdown |= SEND_SHUTDOWN;
 658                         sk->sk_state_change(sk);
 659                         sock_set_flag(sk, SOCK_DEAD);
 660                         sock_set_flag(sk, SOCK_DESTROY);
 661                         break;
 662
 663                 case X25_STATE_5:
 664                         x25_write_internal(sk, X25_CLEAR_REQUEST);
 665                         x25_disconnect(sk, 0, 0, 0);
 666                         __x25_destroy_socket(sk);
 667                         goto out;
 668         }
 669
 670         sock_orphan(sk);
 671 out:
 672         release_sock(sk);
 673         sock_put(sk);
 674         return 0;
 675 }
 676
 677 static int x25_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
 678 {
 679         struct sock *sk = sock->sk;
 680         struct sockaddr_x25 *addr = (struct sockaddr_x25 *)uaddr;
 681         int len, i, rc = 0;
 682
 683         if (addr_len != sizeof(struct sockaddr_x25) ||
 684             addr->sx25_family != AF_X25) {
 685                 rc = -EINVAL;
 686                 goto out;
 687         }
 688
 689         /* check for the null_x25_address */
 690         if (strcmp(addr->sx25_addr.x25_addr, null_x25_address.x25_addr)) {
 691
 692                 len = strlen(addr->sx25_addr.x25_addr);
 693                 for (i = 0; i < len; i++) {
 694                         if (!isdigit(addr->sx25_addr.x25_addr[i])) {
 695                                 rc = -EINVAL;
 696                                 goto out;
 697                         }
 698                 }
 699         }
 700
 701         lock_sock(sk);
 702         if (sock_flag(sk, SOCK_ZAPPED)) {
 703                 x25_sk(sk)->source_addr = addr->sx25_addr;
 704                 x25_insert_socket(sk);
 705                 sock_reset_flag(sk, SOCK_ZAPPED);
 706         } else {
 707                 rc = -EINVAL;
 708         }
 709         release_sock(sk);
 710         SOCK_DEBUG(sk, "x25_bind: socket is bound\n");
 711 out:
 712         return rc;
 713 }
 714
 715 static int x25_wait_for_connection_establishment(struct sock *sk)
 716 {
 717         DECLARE_WAITQUEUE(wait, current);
 718         int rc;
 719
 720         add_wait_queue_exclusive(sk_sleep(sk), &wait);
 721         for (;;) {
 722                 __set_current_state(TASK_INTERRUPTIBLE);
 723                 rc = -ERESTARTSYS;
 724                 if (signal_pending(current))
 725                         break;
 726                 rc = sock_error(sk);
 727                 if (rc) {
 728                         sk->sk_socket->state = SS_UNCONNECTED;
 729                         break;
 730                 }
 731                 rc = 0;
 732                 if (sk->sk_state != TCP_ESTABLISHED) {
 733                         release_sock(sk);
 734                         schedule();
 735                         lock_sock(sk);
 736                 } else
 737                         break;
 738         }
 739         __set_current_state(TASK_RUNNING);
 740         remove_wait_queue(sk_sleep(sk), &wait);
 741         return rc;
 742 }
 743
 744 static int x25_connect(struct socket *sock, struct sockaddr *uaddr,
 745                        int addr_len, int flags)
 746 {
 747         struct sock *sk = sock->sk;
 748         struct x25_sock *x25 = x25_sk(sk);
 749         struct sockaddr_x25 *addr = (struct sockaddr_x25 *)uaddr;
 750         struct x25_route *rt;
 751         int rc = 0;
 752
 753         lock_sock(sk);
 754         if (sk->sk_state == TCP_ESTABLISHED && sock->state == SS_CONNECTING) {
 755                 sock->state = SS_CONNECTED;
 756                 goto out; /* Connect completed during a ERESTARTSYS event */
 757         }
 758
 759         rc = -ECONNREFUSED;
 760         if (sk->sk_state == TCP_CLOSE && sock->state == SS_CONNECTING) {
 761                 sock->state = SS_UNCONNECTED;
 762                 goto out;
 763         }
 764
 765         rc = -EISCONN;  /* No reconnect on a seqpacket socket */
 766         if (sk->sk_state == TCP_ESTABLISHED)
 767                 goto out;
 768
 769         rc = -EALREADY; /* Do nothing if call is already in progress */
 770         if (sk->sk_state == TCP_SYN_SENT)
 771                 goto out;
 772
 773         sk->sk_state   = TCP_CLOSE;
 774         sock->state = SS_UNCONNECTED;
 775
 776         rc = -EINVAL;
 777         if (addr_len != sizeof(struct sockaddr_x25) ||
 778             addr->sx25_family != AF_X25)
 779                 goto out;
 780
 781         rc = -ENETUNREACH;
 782         rt = x25_get_route(&addr->sx25_addr);
 783         if (!rt)
 784                 goto out;
 785
 786         x25->neighbour = x25_get_neigh(rt->dev);
 787         if (!x25->neighbour)
 788                 goto out_put_route;
 789
 790         x25_limit_facilities(&x25->facilities, x25->neighbour);
 791
 792         x25->lci = x25_new_lci(x25->neighbour);
 793         if (!x25->lci)
 794                 goto out_put_neigh;
 795
 796         rc = -EINVAL;
 797         if (sock_flag(sk, SOCK_ZAPPED)) /* Must bind first - autobinding does not work */
 798                 goto out_put_neigh;
 799
 800         if (!strcmp(x25->source_addr.x25_addr, null_x25_address.x25_addr))
 801                 memset(&x25->source_addr, '\0', X25_ADDR_LEN);
 802
 803         x25->dest_addr = addr->sx25_addr;
 804
 805         /* Move to connecting socket, start sending Connect Requests */
 806         sock->state   = SS_CONNECTING;
 807         sk->sk_state  = TCP_SYN_SENT;
 808
 809         x25->state = X25_STATE_1;
 810
 811         x25_write_internal(sk, X25_CALL_REQUEST);
 812
 813         x25_start_heartbeat(sk);
 814         x25_start_t21timer(sk);
 815
 816         /* Now the loop */
 817         rc = -EINPROGRESS;
 818         if (sk->sk_state != TCP_ESTABLISHED && (flags & O_NONBLOCK))
 819                 goto out;
 820
 821         rc = x25_wait_for_connection_establishment(sk);
 822         if (rc)
 823                 goto out_put_neigh;
 824
 825         sock->state = SS_CONNECTED;
 826         rc = 0;
 827 out_put_neigh:
 828         if (rc) {
 829                 read_lock_bh(&x25_list_lock);
 830                 x25_neigh_put(x25->neighbour);
 831                 x25->neighbour = NULL;
 832                 read_unlock_bh(&x25_list_lock);
 833                 x25->state = X25_STATE_0;
 834         }
 835 out_put_route:
 836         x25_route_put(rt);
 837 out:
 838         release_sock(sk);
 839         return rc;
 840 }
 841
 842 static int x25_wait_for_data(struct sock *sk, long timeout)
 843 {
 844         DECLARE_WAITQUEUE(wait, current);
 845         int rc = 0;
 846
 847         add_wait_queue_exclusive(sk_sleep(sk), &wait);
 848         for (;;) {
 849                 __set_current_state(TASK_INTERRUPTIBLE);
 850                 if (sk->sk_shutdown & RCV_SHUTDOWN)
 851                         break;
 852                 rc = -ERESTARTSYS;
 853                 if (signal_pending(current))
 854                         break;
 855                 rc = -EAGAIN;
 856                 if (!timeout)
 857                         break;
 858                 rc = 0;
 859                 if (skb_queue_empty(&sk->sk_receive_queue)) {
 860                         release_sock(sk);
 861                         timeout = schedule_timeout(timeout);
 862                         lock_sock(sk);
 863                 } else
 864                         break;
 865         }
 866         __set_current_state(TASK_RUNNING);
 867         remove_wait_queue(sk_sleep(sk), &wait);
 868         return rc;
 869 }
 870
 871 static int x25_accept(struct socket *sock, struct socket *newsock, int flags,
 872                       bool kern)
 873 {
 874         struct sock *sk = sock->sk;
 875         struct sock *newsk;
 876         struct sk_buff *skb;
 877         int rc = -EINVAL;
 878
 879         if (!sk)
 880                 goto out;
 881
 882         rc = -EOPNOTSUPP;
 883         if (sk->sk_type != SOCK_SEQPACKET)
 884                 goto out;
 885
 886         lock_sock(sk);
 887         rc = -EINVAL;
 888         if (sk->sk_state != TCP_LISTEN)
 889                 goto out2;
 890
 891         rc = x25_wait_for_data(sk, sk->sk_rcvtimeo);
 892         if (rc)
 893                 goto out2;
 894         skb = skb_dequeue(&sk->sk_receive_queue);
 895         rc = -EINVAL;
 896         if (!skb->sk)
 897                 goto out2;
 898         newsk            = skb->sk;
 899         sock_graft(newsk, newsock);
 900
 901         /* Now attach up the new socket */
 902         skb->sk = NULL;
 903         kfree_skb(skb);
 904         sk_acceptq_removed(sk);
 905         newsock->state = SS_CONNECTED;
 906         rc = 0;
 907 out2:
 908         release_sock(sk);
 909 out:
 910         return rc;
 911 }
 912
 913 static int x25_getname(struct socket *sock, struct sockaddr *uaddr,
 914                        int peer)
 915 {
 916         struct sockaddr_x25 *sx25 = (struct sockaddr_x25 *)uaddr;
 917         struct sock *sk = sock->sk;
 918         struct x25_sock *x25 = x25_sk(sk);
 919         int rc = 0;
 920
 921         if (peer) {
 922                 if (sk->sk_state != TCP_ESTABLISHED) {
 923                         rc = -ENOTCONN;
 924                         goto out;
 925                 }
 926                 sx25->sx25_addr = x25->dest_addr;
 927         } else
 928                 sx25->sx25_addr = x25->source_addr;
 929
 930         sx25->sx25_family = AF_X25;
 931         rc = sizeof(*sx25);
 932
 933 out:
 934         return rc;
 935 }
 936
 937 int x25_rx_call_request(struct sk_buff *skb, struct x25_neigh *nb,
 938                         unsigned int lci)
 939 {
 940         struct sock *sk;
 941         struct sock *make;
 942         struct x25_sock *makex25;
 943         struct x25_address source_addr, dest_addr;
 944         struct x25_facilities facilities;
 945         struct x25_dte_facilities dte_facilities;
 946         int len, addr_len, rc;
 947
 948         /*
 949          *      Remove the LCI and frame type.
 950          */
 951         skb_pull(skb, X25_STD_MIN_LEN);
 952
 953         /*
 954          *      Extract the X.25 addresses and convert them to ASCII strings,
 955          *      and remove them.
 956          *
 957          *      Address block is mandatory in call request packets
 958          */
 959         addr_len = x25_parse_address_block(skb, &source_addr, &dest_addr);
 960         if (addr_len <= 0)
 961                 goto out_clear_request;
 962         skb_pull(skb, addr_len);
 963
 964         /*
 965          *      Get the length of the facilities, skip past them for the moment
 966          *      get the call user data because this is needed to determine
 967          *      the correct listener
 968          *
 969          *      Facilities length is mandatory in call request packets
 970          */
 971         if (!pskb_may_pull(skb, 1))
 972                 goto out_clear_request;
 973         len = skb->data[0] + 1;
 974         if (!pskb_may_pull(skb, len))
 975                 goto out_clear_request;
 976         skb_pull(skb,len);
 977
 978         /*
 979          *      Ensure that the amount of call user data is valid.
 980          */
 981         if (skb->len > X25_MAX_CUD_LEN)
 982                 goto out_clear_request;
 983
 984         /*
 985          *      Get all the call user data so it can be used in
 986          *      x25_find_listener and skb_copy_from_linear_data up ahead.
 987          */
 988         if (!pskb_may_pull(skb, skb->len))
 989                 goto out_clear_request;
 990
 991         /*
 992          *      Find a listener for the particular address/cud pair.
 993          */
 994         sk = x25_find_listener(&source_addr,skb);
 995         skb_push(skb,len);
 996
 997         if (sk != NULL && sk_acceptq_is_full(sk)) {
 998                 goto out_sock_put;
 999         }
1000
1001         /*
1002          *      We dont have any listeners for this incoming call.
1003          *      Try forwarding it.
1004          */
1005         if (sk == NULL) {
1006                 skb_push(skb, addr_len + X25_STD_MIN_LEN);
1007                 if (sysctl_x25_forward &&
1008                                 x25_forward_call(&dest_addr, nb, skb, lci) > 0)
1009                 {
1010                         /* Call was forwarded, dont process it any more */
1011                         kfree_skb(skb);
1012                         rc = 1;
1013                         goto out;
1014                 } else {
1015                         /* No listeners, can't forward, clear the call */
1016                         goto out_clear_request;
1017                 }
1018         }
1019
1020         /*
1021          *      Try to reach a compromise on the requested facilities.
1022          */
1023         len = x25_negotiate_facilities(skb, sk, &facilities, &dte_facilities);
1024         if (len == -1)
1025                 goto out_sock_put;
1026
1027         /*
1028          * current neighbour/link might impose additional limits
1029          * on certain facilties
1030          */
1031
1032         x25_limit_facilities(&facilities, nb);
1033
1034         /*
1035          *      Try to create a new socket.
1036          */
1037         make = x25_make_new(sk);
1038         if (!make)
1039                 goto out_sock_put;
1040
1041         /*
1042          *      Remove the facilities
1043          */
1044         skb_pull(skb, len);
1045
1046         skb->sk     = make;
1047         make->sk_state = TCP_ESTABLISHED;
1048
1049         makex25 = x25_sk(make);
1050         makex25->lci           = lci;
1051         makex25->dest_addr     = dest_addr;
1052         makex25->source_addr   = source_addr;
1053         makex25->neighbour     = nb;
1054         makex25->facilities    = facilities;
1055         makex25->dte_facilities= dte_facilities;
1056         makex25->vc_facil_mask = x25_sk(sk)->vc_facil_mask;
1057         /* ensure no reverse facil on accept */
1058         makex25->vc_facil_mask &= ~X25_MASK_REVERSE;
1059         /* ensure no calling address extension on accept */
1060         makex25->vc_facil_mask &= ~X25_MASK_CALLING_AE;
1061         makex25->cudmatchlength = x25_sk(sk)->cudmatchlength;
1062
1063         /* Normally all calls are accepted immediately */
1064         if (test_bit(X25_ACCPT_APPRV_FLAG, &makex25->flags)) {
1065                 x25_write_internal(make, X25_CALL_ACCEPTED);
1066                 makex25->state = X25_STATE_3;
1067         } else {
1068                 makex25->state = X25_STATE_5;
1069         }
1070
1071         /*
1072          *      Incoming Call User Data.
1073          */
1074         skb_copy_from_linear_data(skb, makex25->calluserdata.cuddata, skb->len);
1075         makex25->calluserdata.cudlength = skb->len;
1076
1077         sk_acceptq_added(sk);
1078
1079         x25_insert_socket(make);
1080
1081         skb_queue_head(&sk->sk_receive_queue, skb);
1082
1083         x25_start_heartbeat(make);
1084
1085         if (!sock_flag(sk, SOCK_DEAD))
1086                 sk->sk_data_ready(sk);
1087         rc = 1;
1088         sock_put(sk);
1089 out:
1090         return rc;
1091 out_sock_put:
1092         sock_put(sk);
1093 out_clear_request:
1094         rc = 0;
1095         x25_transmit_clear_request(nb, lci, 0x01);
1096         goto out;
1097 }
1098
1099 static int x25_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
1100 {
1101         struct sock *sk = sock->sk;
1102         struct x25_sock *x25 = x25_sk(sk);
1103         DECLARE_SOCKADDR(struct sockaddr_x25 *, usx25, msg->msg_name);
1104         struct sockaddr_x25 sx25;
1105         struct sk_buff *skb;
1106         unsigned char *asmptr;
1107         int noblock = msg->msg_flags & MSG_DONTWAIT;
1108         size_t size;
1109         int qbit = 0, rc = -EINVAL;
1110
1111         lock_sock(sk);
1112         if (msg->msg_flags & ~(MSG_DONTWAIT|MSG_OOB|MSG_EOR|MSG_CMSG_COMPAT))
1113                 goto out;
1114
1115         /* we currently don't support segmented records at the user interface */
1116         if (!(msg->msg_flags & (MSG_EOR|MSG_OOB)))
1117                 goto out;
1118
1119         rc = -EADDRNOTAVAIL;
1120         if (sock_flag(sk, SOCK_ZAPPED))
1121                 goto out;
1122
1123         rc = -EPIPE;
1124         if (sk->sk_shutdown & SEND_SHUTDOWN) {
1125                 send_sig(SIGPIPE, current, 0);
1126                 goto out;
1127         }
1128
1129         rc = -ENETUNREACH;
1130         if (!x25->neighbour)
1131                 goto out;
1132
1133         if (usx25) {
1134                 rc = -EINVAL;
1135                 if (msg->msg_namelen < sizeof(sx25))
1136                         goto out;
1137                 memcpy(&sx25, usx25, sizeof(sx25));
1138                 rc = -EISCONN;
1139                 if (strcmp(x25->dest_addr.x25_addr, sx25.sx25_addr.x25_addr))
1140                         goto out;
1141                 rc = -EINVAL;
1142                 if (sx25.sx25_family != AF_X25)
1143                         goto out;
1144         } else {
1145                 /*
1146                  *      FIXME 1003.1g - if the socket is like this because
1147                  *      it has become closed (not started closed) we ought
1148                  *      to SIGPIPE, EPIPE;
1149                  */
1150                 rc = -ENOTCONN;
1151                 if (sk->sk_state != TCP_ESTABLISHED)
1152                         goto out;
1153
1154                 sx25.sx25_family = AF_X25;
1155                 sx25.sx25_addr   = x25->dest_addr;
1156         }
1157
1158         /* Sanity check the packet size */
1159         if (len > 65535) {
1160                 rc = -EMSGSIZE;
1161                 goto out;
1162         }
1163
1164         SOCK_DEBUG(sk, "x25_sendmsg: sendto: Addresses built.\n");
1165
1166         /* Build a packet */
1167         SOCK_DEBUG(sk, "x25_sendmsg: sendto: building packet.\n");
1168
1169         if ((msg->msg_flags & MSG_OOB) && len > 32)
1170                 len = 32;
1171
1172         size = len + X25_MAX_L2_LEN + X25_EXT_MIN_LEN;
1173
1174         release_sock(sk);
1175         skb = sock_alloc_send_skb(sk, size, noblock, &rc);
1176         lock_sock(sk);
1177         if (!skb)
1178                 goto out;
1179         X25_SKB_CB(skb)->flags = msg->msg_flags;
1180
1181         skb_reserve(skb, X25_MAX_L2_LEN + X25_EXT_MIN_LEN);
1182
1183         /*
1184          *      Put the data on the end
1185          */
1186         SOCK_DEBUG(sk, "x25_sendmsg: Copying user data\n");
1187
1188         skb_reset_transport_header(skb);
1189         skb_put(skb, len);
1190
1191         rc = memcpy_from_msg(skb_transport_header(skb), msg, len);
1192         if (rc)
1193                 goto out_kfree_skb;
1194
1195         /*
1196          *      If the Q BIT Include socket option is in force, the first
1197          *      byte of the user data is the logical value of the Q Bit.
1198          */
1199         if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1200                 if (!pskb_may_pull(skb, 1))
1201                         goto out_kfree_skb;
1202
1203                 qbit = skb->data[0];
1204                 skb_pull(skb, 1);
1205         }
1206
1207         /*
1208          *      Push down the X.25 header
1209          */
1210         SOCK_DEBUG(sk, "x25_sendmsg: Building X.25 Header.\n");
1211
1212         if (msg->msg_flags & MSG_OOB) {
1213                 if (x25->neighbour->extended) {
1214                         asmptr    = skb_push(skb, X25_STD_MIN_LEN);
1215                         *asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_EXTSEQ;
1216                         *asmptr++ = (x25->lci >> 0) & 0xFF;
1217                         *asmptr++ = X25_INTERRUPT;
1218                 } else {
1219                         asmptr    = skb_push(skb, X25_STD_MIN_LEN);
1220                         *asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_STDSEQ;
1221                         *asmptr++ = (x25->lci >> 0) & 0xFF;
1222                         *asmptr++ = X25_INTERRUPT;
1223                 }
1224         } else {
1225                 if (x25->neighbour->extended) {
1226                         /* Build an Extended X.25 header */
1227                         asmptr    = skb_push(skb, X25_EXT_MIN_LEN);
1228                         *asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_EXTSEQ;
1229                         *asmptr++ = (x25->lci >> 0) & 0xFF;
1230                         *asmptr++ = X25_DATA;
1231                         *asmptr++ = X25_DATA;
1232                 } else {
1233                         /* Build an Standard X.25 header */
1234                         asmptr    = skb_push(skb, X25_STD_MIN_LEN);
1235                         *asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_STDSEQ;
1236                         *asmptr++ = (x25->lci >> 0) & 0xFF;
1237                         *asmptr++ = X25_DATA;
1238                 }
1239
1240                 if (qbit)
1241                         skb->data[0] |= X25_Q_BIT;
1242         }
1243
1244         SOCK_DEBUG(sk, "x25_sendmsg: Built header.\n");
1245         SOCK_DEBUG(sk, "x25_sendmsg: Transmitting buffer\n");
1246
1247         rc = -ENOTCONN;
1248         if (sk->sk_state != TCP_ESTABLISHED)
1249                 goto out_kfree_skb;
1250
1251         if (msg->msg_flags & MSG_OOB)
1252                 skb_queue_tail(&x25->interrupt_out_queue, skb);
1253         else {
1254                 rc = x25_output(sk, skb);
1255                 len = rc;
1256                 if (rc < 0)
1257                         kfree_skb(skb);
1258                 else if (test_bit(X25_Q_BIT_FLAG, &x25->flags))
1259                         len++;
1260         }
1261
1262         x25_kick(sk);
1263         rc = len;
1264 out:
1265         release_sock(sk);
1266         return rc;
1267 out_kfree_skb:
1268         kfree_skb(skb);
1269         goto out;
1270 }
1271
1272
1273 static int x25_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1274                        int flags)
1275 {
1276         struct sock *sk = sock->sk;
1277         struct x25_sock *x25 = x25_sk(sk);
1278         DECLARE_SOCKADDR(struct sockaddr_x25 *, sx25, msg->msg_name);
1279         size_t copied;
1280         int qbit, header_len;
1281         struct sk_buff *skb;
1282         unsigned char *asmptr;
1283         int rc = -ENOTCONN;
1284
1285         lock_sock(sk);
1286
1287         if (x25->neighbour == NULL)
1288                 goto out;
1289
1290         header_len = x25->neighbour->extended ?
1291                 X25_EXT_MIN_LEN : X25_STD_MIN_LEN;
1292
1293         /*
1294          * This works for seqpacket too. The receiver has ordered the queue for
1295          * us! We do one quick check first though
1296          */
1297         if (sk->sk_state != TCP_ESTABLISHED)
1298                 goto out;
1299
1300         if (flags & MSG_OOB) {
1301                 rc = -EINVAL;
1302                 if (sock_flag(sk, SOCK_URGINLINE) ||
1303                     !skb_peek(&x25->interrupt_in_queue))
1304                         goto out;
1305
1306                 skb = skb_dequeue(&x25->interrupt_in_queue);
1307
1308                 if (!pskb_may_pull(skb, X25_STD_MIN_LEN))
1309                         goto out_free_dgram;
1310
1311                 skb_pull(skb, X25_STD_MIN_LEN);
1312
1313                 /*
1314                  *      No Q bit information on Interrupt data.
1315                  */
1316                 if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1317                         asmptr  = skb_push(skb, 1);
1318                         *asmptr = 0x00;
1319                 }
1320
1321                 msg->msg_flags |= MSG_OOB;
1322         } else {
1323                 /* Now we can treat all alike */
1324                 release_sock(sk);
1325                 skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT,
1326                                         flags & MSG_DONTWAIT, &rc);
1327                 lock_sock(sk);
1328                 if (!skb)
1329                         goto out;
1330
1331                 if (!pskb_may_pull(skb, header_len))
1332                         goto out_free_dgram;
1333
1334                 qbit = (skb->data[0] & X25_Q_BIT) == X25_Q_BIT;
1335
1336                 skb_pull(skb, header_len);
1337
1338                 if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) {
1339                         asmptr  = skb_push(skb, 1);
1340                         *asmptr = qbit;
1341                 }
1342         }
1343
1344         skb_reset_transport_header(skb);
1345         copied = skb->len;
1346
1347         if (copied > size) {
1348                 copied = size;
1349                 msg->msg_flags |= MSG_TRUNC;
1350         }
1351
1352         /* Currently, each datagram always contains a complete record */
1353         msg->msg_flags |= MSG_EOR;
1354
1355         rc = skb_copy_datagram_msg(skb, 0, msg, copied);
1356         if (rc)
1357                 goto out_free_dgram;
1358
1359         if (sx25) {
1360                 sx25->sx25_family = AF_X25;
1361                 sx25->sx25_addr   = x25->dest_addr;
1362                 msg->msg_namelen = sizeof(*sx25);
1363         }
1364
1365         x25_check_rbuf(sk);
1366         rc = copied;
1367 out_free_dgram:
1368         skb_free_datagram(sk, skb);
1369 out:
1370         release_sock(sk);
1371         return rc;
1372 }
1373
1374
1375 static int x25_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
1376 {
1377         struct sock *sk = sock->sk;
1378         struct x25_sock *x25 = x25_sk(sk);
1379         void __user *argp = (void __user *)arg;
1380         int rc;
1381
1382         switch (cmd) {
1383         case TIOCOUTQ: {
1384                 int amount;
1385
1386                 amount = sk->sk_sndbuf - sk_wmem_alloc_get(sk);
1387                 if (amount < 0)
1388                         amount = 0;
1389                 rc = put_user(amount, (unsigned int __user *)argp);
1390                 break;
1391         }
1392
1393         case TIOCINQ: {
1394                 struct sk_buff *skb;
1395                 int amount = 0;
1396                 /*
1397                  * These two are safe on a single CPU system as
1398                  * only user tasks fiddle here
1399                  */
1400                 lock_sock(sk);
1401                 if ((skb = skb_peek(&sk->sk_receive_queue)) != NULL)
1402                         amount = skb->len;
1403                 release_sock(sk);
1404                 rc = put_user(amount, (unsigned int __user *)argp);
1405                 break;
1406         }
1407
1408         case SIOCGIFADDR:
1409         case SIOCSIFADDR:
1410         case SIOCGIFDSTADDR:
1411         case SIOCSIFDSTADDR:
1412         case SIOCGIFBRDADDR:
1413         case SIOCSIFBRDADDR:
1414         case SIOCGIFNETMASK:
1415         case SIOCSIFNETMASK:
1416         case SIOCGIFMETRIC:
1417         case SIOCSIFMETRIC:
1418                 rc = -EINVAL;
1419                 break;
1420         case SIOCADDRT:
1421         case SIOCDELRT:
1422                 rc = -EPERM;
1423                 if (!capable(CAP_NET_ADMIN))
1424                         break;
1425                 rc = x25_route_ioctl(cmd, argp);
1426                 break;
1427         case SIOCX25GSUBSCRIP:
1428                 rc = x25_subscr_ioctl(cmd, argp);
1429                 break;
1430         case SIOCX25SSUBSCRIP:
1431                 rc = -EPERM;
1432                 if (!capable(CAP_NET_ADMIN))
1433                         break;
1434                 rc = x25_subscr_ioctl(cmd, argp);
1435                 break;
1436         case SIOCX25GFACILITIES: {
1437                 lock_sock(sk);
1438                 rc = copy_to_user(argp, &x25->facilities,
1439                                   sizeof(x25->facilities))
1440                         ? -EFAULT : 0;
1441                 release_sock(sk);
1442                 break;
1443         }
1444
1445         case SIOCX25SFACILITIES: {
1446                 struct x25_facilities facilities;
1447                 rc = -EFAULT;
1448                 if (copy_from_user(&facilities, argp, sizeof(facilities)))
1449                         break;
1450                 rc = -EINVAL;
1451                 lock_sock(sk);
1452                 if (sk->sk_state != TCP_LISTEN &&
1453                     sk->sk_state != TCP_CLOSE)
1454                         goto out_fac_release;
1455                 if (facilities.pacsize_in < X25_PS16 ||
1456                     facilities.pacsize_in > X25_PS4096)
1457                         goto out_fac_release;
1458                 if (facilities.pacsize_out < X25_PS16 ||
1459                     facilities.pacsize_out > X25_PS4096)
1460                         goto out_fac_release;
1461                 if (facilities.winsize_in < 1 ||
1462                     facilities.winsize_in > 127)
1463                         goto out_fac_release;
1464                 if (facilities.throughput) {
1465                         int out = facilities.throughput & 0xf0;
1466                         int in  = facilities.throughput & 0x0f;
1467                         if (!out)
1468                                 facilities.throughput |=
1469                                         X25_DEFAULT_THROUGHPUT << 4;
1470                         else if (out < 0x30 || out > 0xD0)
1471                                 goto out_fac_release;
1472                         if (!in)
1473                                 facilities.throughput |=
1474                                         X25_DEFAULT_THROUGHPUT;
1475                         else if (in < 0x03 || in > 0x0D)
1476                                 goto out_fac_release;
1477                 }
1478                 if (facilities.reverse &&
1479                     (facilities.reverse & 0x81) != 0x81)
1480                         goto out_fac_release;
1481                 x25->facilities = facilities;
1482                 rc = 0;
1483 out_fac_release:
1484                 release_sock(sk);
1485                 break;
1486         }
1487
1488         case SIOCX25GDTEFACILITIES: {
1489                 lock_sock(sk);
1490                 rc = copy_to_user(argp, &x25->dte_facilities,
1491                                   sizeof(x25->dte_facilities));
1492                 release_sock(sk);
1493                 if (rc)
1494                         rc = -EFAULT;
1495                 break;
1496         }
1497
1498         case SIOCX25SDTEFACILITIES: {
1499                 struct x25_dte_facilities dtefacs;
1500                 rc = -EFAULT;
1501                 if (copy_from_user(&dtefacs, argp, sizeof(dtefacs)))
1502                         break;
1503                 rc = -EINVAL;
1504                 lock_sock(sk);
1505                 if (sk->sk_state != TCP_LISTEN &&
1506                     sk->sk_state != TCP_CLOSE)
1507                         goto out_dtefac_release;
1508                 if (dtefacs.calling_len > X25_MAX_AE_LEN)
1509                         goto out_dtefac_release;
1510                 if (dtefacs.called_len > X25_MAX_AE_LEN)
1511                         goto out_dtefac_release;
1512                 x25->dte_facilities = dtefacs;
1513                 rc = 0;
1514 out_dtefac_release:
1515                 release_sock(sk);
1516                 break;
1517         }
1518
1519         case SIOCX25GCALLUSERDATA: {
1520                 lock_sock(sk);
1521                 rc = copy_to_user(argp, &x25->calluserdata,
1522                                   sizeof(x25->calluserdata))
1523                         ? -EFAULT : 0;
1524                 release_sock(sk);
1525                 break;
1526         }
1527
1528         case SIOCX25SCALLUSERDATA: {
1529                 struct x25_calluserdata calluserdata;
1530
1531                 rc = -EFAULT;
1532                 if (copy_from_user(&calluserdata, argp, sizeof(calluserdata)))
1533                         break;
1534                 rc = -EINVAL;
1535                 if (calluserdata.cudlength > X25_MAX_CUD_LEN)
1536                         break;
1537                 lock_sock(sk);
1538                 x25->calluserdata = calluserdata;
1539                 release_sock(sk);
1540                 rc = 0;
1541                 break;
1542         }
1543
1544         case SIOCX25GCAUSEDIAG: {
1545                 lock_sock(sk);
1546                 rc = copy_to_user(argp, &x25->causediag, sizeof(x25->causediag))
1547                         ? -EFAULT : 0;
1548                 release_sock(sk);
1549                 break;
1550         }
1551
1552         case SIOCX25SCAUSEDIAG: {
1553                 struct x25_causediag causediag;
1554                 rc = -EFAULT;
1555                 if (copy_from_user(&causediag, argp, sizeof(causediag)))
1556                         break;
1557                 lock_sock(sk);
1558                 x25->causediag = causediag;
1559                 release_sock(sk);
1560                 rc = 0;
1561                 break;
1562
1563         }
1564
1565         case SIOCX25SCUDMATCHLEN: {
1566                 struct x25_subaddr sub_addr;
1567                 rc = -EINVAL;
1568                 lock_sock(sk);
1569                 if(sk->sk_state != TCP_CLOSE)
1570                         goto out_cud_release;
1571                 rc = -EFAULT;
1572                 if (copy_from_user(&sub_addr, argp,
1573                                    sizeof(sub_addr)))
1574                         goto out_cud_release;
1575                 rc = -EINVAL;
1576                 if (sub_addr.cudmatchlength > X25_MAX_CUD_LEN)
1577                         goto out_cud_release;
1578                 x25->cudmatchlength = sub_addr.cudmatchlength;
1579                 rc = 0;
1580 out_cud_release:
1581                 release_sock(sk);
1582                 break;
1583         }
1584
1585         case SIOCX25CALLACCPTAPPRV: {
1586                 rc = -EINVAL;
1587                 lock_sock(sk);
1588                 if (sk->sk_state == TCP_CLOSE) {
1589                         clear_bit(X25_ACCPT_APPRV_FLAG, &x25->flags);
1590                         rc = 0;
1591                 }
1592                 release_sock(sk);
1593                 break;
1594         }
1595
1596         case SIOCX25SENDCALLACCPT:  {
1597                 rc = -EINVAL;
1598                 lock_sock(sk);
1599                 if (sk->sk_state != TCP_ESTABLISHED)
1600                         goto out_sendcallaccpt_release;
1601                 /* must call accptapprv above */
1602                 if (test_bit(X25_ACCPT_APPRV_FLAG, &x25->flags))
1603                         goto out_sendcallaccpt_release;
1604                 x25_write_internal(sk, X25_CALL_ACCEPTED);
1605                 x25->state = X25_STATE_3;
1606                 rc = 0;
1607 out_sendcallaccpt_release:
1608                 release_sock(sk);
1609                 break;
1610         }
1611
1612         default:
1613                 rc = -ENOIOCTLCMD;
1614                 break;
1615         }
1616
1617         return rc;
1618 }
1619
1620 static const struct net_proto_family x25_family_ops = {
1621         .family =       AF_X25,
1622         .create =       x25_create,
1623         .owner  =       THIS_MODULE,
1624 };
1625
1626 #ifdef CONFIG_COMPAT
1627 static int compat_x25_subscr_ioctl(unsigned int cmd,
1628                 struct compat_x25_subscrip_struct __user *x25_subscr32)
1629 {
1630         struct compat_x25_subscrip_struct x25_subscr;
1631         struct x25_neigh *nb;
1632         struct net_device *dev;
1633         int rc = -EINVAL;
1634
1635         rc = -EFAULT;
1636         if (copy_from_user(&x25_subscr, x25_subscr32, sizeof(*x25_subscr32)))
1637                 goto out;
1638
1639         rc = -EINVAL;
1640         dev = x25_dev_get(x25_subscr.device);
1641         if (dev == NULL)
1642                 goto out;
1643
1644         nb = x25_get_neigh(dev);
1645         if (nb == NULL)
1646                 goto out_dev_put;
1647
1648         dev_put(dev);
1649
1650         if (cmd == SIOCX25GSUBSCRIP) {
1651                 read_lock_bh(&x25_neigh_list_lock);
1652                 x25_subscr.extended = nb->extended;
1653                 x25_subscr.global_facil_mask = nb->global_facil_mask;
1654                 read_unlock_bh(&x25_neigh_list_lock);
1655                 rc = copy_to_user(x25_subscr32, &x25_subscr,
1656                                 sizeof(*x25_subscr32)) ? -EFAULT : 0;
1657         } else {
1658                 rc = -EINVAL;
1659                 if (x25_subscr.extended == 0 || x25_subscr.extended == 1) {
1660                         rc = 0;
1661                         write_lock_bh(&x25_neigh_list_lock);
1662                         nb->extended = x25_subscr.extended;
1663                         nb->global_facil_mask = x25_subscr.global_facil_mask;
1664                         write_unlock_bh(&x25_neigh_list_lock);
1665                 }
1666         }
1667         x25_neigh_put(nb);
1668 out:
1669         return rc;
1670 out_dev_put:
1671         dev_put(dev);
1672         goto out;
1673 }
1674
1675 static int compat_x25_ioctl(struct socket *sock, unsigned int cmd,
1676                                 unsigned long arg)
1677 {
1678         void __user *argp = compat_ptr(arg);
1679         int rc = -ENOIOCTLCMD;
1680
1681         switch(cmd) {
1682         case TIOCOUTQ:
1683         case TIOCINQ:
1684                 rc = x25_ioctl(sock, cmd, (unsigned long)argp);
1685                 break;
1686         case SIOCGIFADDR:
1687         case SIOCSIFADDR:
1688         case SIOCGIFDSTADDR:
1689         case SIOCSIFDSTADDR:
1690         case SIOCGIFBRDADDR:
1691         case SIOCSIFBRDADDR:
1692         case SIOCGIFNETMASK:
1693         case SIOCSIFNETMASK:
1694         case SIOCGIFMETRIC:
1695         case SIOCSIFMETRIC:
1696                 rc = -EINVAL;
1697                 break;
1698         case SIOCADDRT:
1699         case SIOCDELRT:
1700                 rc = -EPERM;
1701                 if (!capable(CAP_NET_ADMIN))
1702                         break;
1703                 rc = x25_route_ioctl(cmd, argp);
1704                 break;
1705         case SIOCX25GSUBSCRIP:
1706                 rc = compat_x25_subscr_ioctl(cmd, argp);
1707                 break;
1708         case SIOCX25SSUBSCRIP:
1709                 rc = -EPERM;
1710                 if (!capable(CAP_NET_ADMIN))
1711                         break;
1712                 rc = compat_x25_subscr_ioctl(cmd, argp);
1713                 break;
1714         case SIOCX25GFACILITIES:
1715         case SIOCX25SFACILITIES:
1716         case SIOCX25GDTEFACILITIES:
1717         case SIOCX25SDTEFACILITIES:
1718         case SIOCX25GCALLUSERDATA:
1719         case SIOCX25SCALLUSERDATA:
1720         case SIOCX25GCAUSEDIAG:
1721         case SIOCX25SCAUSEDIAG:
1722         case SIOCX25SCUDMATCHLEN:
1723         case SIOCX25CALLACCPTAPPRV:
1724         case SIOCX25SENDCALLACCPT:
1725                 rc = x25_ioctl(sock, cmd, (unsigned long)argp);
1726                 break;
1727         default:
1728                 rc = -ENOIOCTLCMD;
1729                 break;
1730         }
1731         return rc;
1732 }
1733 #endif
1734
1735 static const struct proto_ops x25_proto_ops = {
1736         .family =       AF_X25,
1737         .owner =        THIS_MODULE,
1738         .release =      x25_release,
1739         .bind =         x25_bind,
1740         .connect =      x25_connect,
1741         .socketpair =   sock_no_socketpair,
1742         .accept =       x25_accept,
1743         .getname =      x25_getname,
1744         .poll =         datagram_poll,
1745         .ioctl =        x25_ioctl,
1746 #ifdef CONFIG_COMPAT
1747         .compat_ioctl = compat_x25_ioctl,
1748 #endif
1749         .gettstamp =    sock_gettstamp,
1750         .listen =       x25_listen,
1751         .shutdown =     sock_no_shutdown,
1752         .setsockopt =   x25_setsockopt,
1753         .getsockopt =   x25_getsockopt,
1754         .sendmsg =      x25_sendmsg,
1755         .recvmsg =      x25_recvmsg,
1756         .mmap =         sock_no_mmap,
1757         .sendpage =     sock_no_sendpage,
1758 };
1759
1760 static struct packet_type x25_packet_type __read_mostly = {
1761         .type = cpu_to_be16(ETH_P_X25),
1762         .func = x25_lapb_receive_frame,
1763 };
1764
1765 static struct notifier_block x25_dev_notifier = {
1766         .notifier_call = x25_device_event,
1767 };
1768
1769 void x25_kill_by_neigh(struct x25_neigh *nb)
1770 {
1771         struct sock *s;
1772
1773         write_lock_bh(&x25_list_lock);
1774
1775         sk_for_each(s, &x25_list)
1776                 if (x25_sk(s)->neighbour == nb)
1777                         x25_disconnect(s, ENETUNREACH, 0, 0);
1778
1779         write_unlock_bh(&x25_list_lock);
1780
1781         /* Remove any related forwards */
1782         x25_clear_forward_by_dev(nb->dev);
1783 }
1784
1785 static int __init x25_init(void)
1786 {
1787         int rc;
1788
1789         rc = proto_register(&x25_proto, 0);
1790         if (rc)
1791                 goto out;
1792
1793         rc = sock_register(&x25_family_ops);
1794         if (rc)
1795                 goto out_proto;
1796
1797         dev_add_pack(&x25_packet_type);
1798
1799         rc = register_netdevice_notifier(&x25_dev_notifier);
1800         if (rc)
1801                 goto out_sock;
1802
1803         rc = x25_register_sysctl();
1804         if (rc)
1805                 goto out_dev;
1806
1807         rc = x25_proc_init();
1808         if (rc)
1809                 goto out_sysctl;
1810
1811         pr_info("Linux Version 0.2\n");
1812
1813 out:
1814         return rc;
1815 out_sysctl:
1816         x25_unregister_sysctl();
1817 out_dev:
1818         unregister_netdevice_notifier(&x25_dev_notifier);
1819 out_sock:
1820         dev_remove_pack(&x25_packet_type);
1821         sock_unregister(AF_X25);
1822 out_proto:
1823         proto_unregister(&x25_proto);
1824         goto out;
1825 }
1826 module_init(x25_init);
1827
1828 static void __exit x25_exit(void)
1829 {
1830         x25_proc_exit();
1831         x25_link_free();
1832         x25_route_free();
1833
1834         x25_unregister_sysctl();
1835
1836         unregister_netdevice_notifier(&x25_dev_notifier);
1837
1838         dev_remove_pack(&x25_packet_type);
1839
1840         sock_unregister(AF_X25);
1841         proto_unregister(&x25_proto);
1842 }
1843 module_exit(x25_exit);
1844
1845 MODULE_AUTHOR("Jonathan Naylor <g4klx@g4klx.demon.co.uk>");
1846 MODULE_DESCRIPTION("The X.25 Packet Layer network layer protocol");
1847 MODULE_LICENSE("GPL");
1848 MODULE_ALIAS_NETPROTO(PF_X25);